[R-sig-Geo] How to adjust two maps with different extent in R

Francisco Rodriguez Sanchez f.rodriguez.sanc at gmail.com
Mon Dec 19 12:28:06 CET 2016


Hi Tianyi,

I think raster::rotate will do what you need

https://www.rdocumentation.org/packages/raster/versions/2.5-8/topics/rotate

Cheers,

Paco


El 19/12/2016 a las 07:50, Zhang Tianyi escribió:
> Two maps with different extents
>
> I am using R to process two maps (raster package). I have two maps with both WGS84 coordinates see figure. [image of map] <https://i.stack.imgur.com/bD84y.png>
>
> But one layer is from -180 to 180 in longitude (the map on surface) another one is from 0 to 360 (the map on the bottom).
>
> I need to adjust the bottom layer to -180 to 180 so that they can match. How can I do that?
>
> I think I need to find all grid greater than 180 and then minus 360. But I cannot find the longitude vector and cannot modify it from the Raster data.
>
> Description of the map is:
>
> class       : RasterLayer
> dimensions  : 94, 192, 18048  (nrow, ncol, ncell)
> resolution  : 1.865234, 1.883872  (x, y)
> extent      : 0, 358.125, -88.542, 88.542  (xmin, xmax, ymin, ymax)
> coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> data source : in memory
> names       : TMAX_2015_01_01
> values      : 220.9, 324.3  (min, max)
>
>
> Regadrs,
> Tianyi Zhang
>
> 	[[alternative HTML version deleted]]
>
> _______________________________________________
> R-sig-Geo mailing list
> R-sig-Geo at r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo

-- 
Dr Francisco Rodriguez-Sanchez
Integrative Ecology Group
Estacion Biologica de Doñana - CSIC
Avda. Americo Vespucio s/n
41092 Sevilla (Spain)
http://bit.ly/frod_san



More information about the R-sig-Geo mailing list